Nanocomposites of Cellulose/Carbonated Hydroxyapatite by Microwave-assisted Fabrication in Ionic Liquid: Characterization and Thermal Stability

Cellulose/carbonated hydroxyapatite (CHA) nanocomposites were successfully prepared in ionic liquid by microwave-assisted method and were characterized by X-ray powder diffraction, thermogravimetric analysis, Fourier transform infrared spectrometry and scanning electron microscopy. Ionic liquid acts simultaneously as a solvent and a microwave absorber for the synthesis of cellulose/CHA nanocomposites. The cellulose in nanocomposites displayed cellulose type II crystalline structure. The XRD and FTIR results confirmed the products as cellulose/CHA nanocomposites. The SEM and TEM results indicated that the aggregated CHA nanorods were observed in the cellulose matrix. The effects of cellulose concentrations and heating methods on the products were also investigated. The density of nanocomposites was increased with higher cellulose concentration. Cellulose/CHA nanocomposites with rough surface were formed in ionic liquid by microwave-assisted method, in contrast to the cellulose/HA nanocomposites with flake-like cellulose and rod-like HA prepared in N,N-dimethylacetamide by the microwave heating. A good example of combining green chemistry and functional materials, the microwave-assisted ionic liquid method for the synthesis of cellulose/CHA nanocomposites is capable to achieve the full product within 30 min. This method is fast, environmentally friendly and suitable for the large-scale production of cellulose-based nanocomposites with minimal environmental impact. This nanocomposite is a very promising candidate in application of bioactive materials.